Scientists at the Wistar Institute in the United States have proposed a new way to create antigens that could be used in the development of an HIV vaccine.

According to a study published in the journal Nature Communication, the so-called native trimer is suitable for producing neutralizing antibodies important for fighting the immunodeficiency virus.

In the past, costly experiments on animal models have been conducted to detect antibodies in candidate vaccines. The key target for neutralizing antibodies is the HIV envelope protein (Env), but a vaccine requires this protein to be in its natural form, called a native-like trimer (NLT). Only then can protein immunogens, the components of an HIV vaccine that induce a potent immune response, be created.

However, experiments with immunization with NLT have shown that antibody production does not occur. In the new research paper, the researchers encoded the Env sequence in DNA and found that in mice, this protein formed a proper native trimer that induced neutralizing antibodies. In addition, the production of CD4+ and CD8+ T-lymphocytes was increased.

Cryo-electron microscopy results showed that antibodies connect to an epitope (a segment of the antigen that triggers an immune response) called C3V5. Antibodies that connect to C3V5 are known to protect animals against SHIV infection, which is a close relative of HIV.

According to the researchers, delivery of immunogens using carrier DNA inside the body could serve as an effective tool for creating vaccines against human immunodeficiency virus.